我正在编写一个面板控件,允许用户最小化面板并隐藏此面板上的组件。 单个THidePanel似乎按预期工作,但是当我将其中两个放在由分割器分隔的表单上时。第一个面板对齐 alLeft ;第二个面板 alClient :
单击第二个面板的按钮时,它不会对最小化或最大化做出反应。这是我的所有代码。为什么不起作用?
const
BoarderSize = 20;
type
TButtonPosition = (topleft, topright, buttomleft, buttomright);
///
/// a panel with a smaller panel inside and a button on the side
///
THidePanel = class(TPanel)
private
{ Private-Deklarationen }
///
/// a smaller working panel
WorkingPanel: TPanel;
FLargeHight: Integer;
FLargeWidth: Integer;
FActivateButton: TButton;
FExpandState: Boolean;
FButtonPosition: TButtonPosition;
FOnActivateBtnClick: TNotifyEvent;
procedure SetButtonPosition(const Value: TButtonPosition);
protected
{ Protected-Deklarationen }
public
{ Public-Deklarationen }
constructor create(aOwner: TComponent); override;
procedure WMSize(var Msg: TWMSize); message WM_SIZE;
procedure HideComponents;
procedure H_ActivateButtonClick(Sender: TObject);
procedure SetState(astate: Boolean);
procedure free;
destructor destroy; override;
published
{ Published-Deklarationen }
property OnActivateButtonClick: TNotifyEvent read FOnActivateBtnClick
write FOnActivateBtnClick;
property ButtonPosition: TButtonPosition read FButtonPosition
write SetButtonPosition;
end;
procedure Register;
implementation
procedure Register;
begin
RegisterComponents('Samples', [THidePanel]);
end;
{ THidePanel }
constructor THidePanel.create(aOwner: TComponent);
begin
inherited;
WorkingPanel := TPanel.create(self);
WorkingPanel.Caption := 'V01';
FActivateButton := TButton.create(self);
FActivateButton.Parent := self;
FActivateButton.Caption := '<';
FActivateButton.OnClick := H_ActivateButtonClick;
FActivateButton.Width := BoarderSize;
FActivateButton.Height := BoarderSize;
WorkingPanel.Caption := '';
FLargeWidth := self.Width;
SetButtonPosition(topright);
end;
destructor THidePanel.destroy;
begin
inherited;
end;
procedure THidePanel.free;
begin
inherited;
WorkingPanel.free;
FActivateButton.free;
end;
procedure THidePanel.HideComponents;
var
i: Integer;
begin
for i := 0 to WorkingPanel.ControlCount - 1 do
WorkingPanel.Controls[i].Visible := False;
end;
procedure THidePanel.WMSize(var Msg: TWMSize);
begin
/// set inner panel size
WorkingPanel.Top := self.Top + BoarderSize;
WorkingPanel.Left := self.Left + BoarderSize;
WorkingPanel.Width := self.Width - 2 * BoarderSize;
WorkingPanel.Height := self.Height - 2 * BoarderSize;
/// move button
SetButtonPosition(FButtonPosition);
end;
procedure THidePanel.H_ActivateButtonClick(Sender: TObject);
begin
/// button is clicked!
///
FExpandState := not FExpandState;
SetState( FExpandState );
///
if (Assigned(FOnActivateBtnClick)) then
FOnActivateBtnClick(self);
end;
procedure THidePanel.SetButtonPosition(const Value: TButtonPosition);
begin
FButtonPosition := Value;
case FButtonPosition of
topleft:
begin
FActivateButton.Left := 0;
FActivateButton.Top := 0;
end;
topright:
begin
FActivateButton.Left := self.Width - BoarderSize;
FActivateButton.Top := 0;
end;
buttomleft:
begin
FActivateButton.Left := 0;
FActivateButton.Top := self.ClientWidth - BoarderSize;
end;
buttomright:
begin
FActivateButton.Top := self.ClientWidth - BoarderSize;
FActivateButton.Left := self.Width - BoarderSize;
end;
else
/// never go here
end;
end;
procedure THidePanel.SetState(astate: Boolean);
begin
if astate then
begin
/// ...
FActivateButton.Caption := '>';
self.Width := BoarderSize;
end
else
begin
/// ...
FActivateButton.Caption := '<';
self.Width := FLargeWidth;
end;
end;
答案 0 :(得分:6)
当Control的Anchors设置为 alClient 时,您无法更改大小。
将第二个面板对齐 alLeft 或 alRight 。如果您想要使用此控件填充表单,请设置表单True
的自动调整大小,或者在调整大小时手动设置控件的最大大小。
答案 1 :(得分:0)
与MohsenB已解释过(+ 1ed)类似,您无法使用Align = alClient
更改控件的大小。但是既然你要将它作为一个组件,我会选择临时更改组件的Align
设置,而不是在设计器代码中处理它:即使其成为组件的一个功能,以便能够设置它Align
属性为alClient
,并在情况需要时让其行为相应。
我认为您正在寻找以下增强功能:
unit Unit2;
interface
uses
Messages, Classes, Controls, StdCtrls, ExtCtrls;
const
BorderSize = 20;
type
TButtonPosition = (bpTopLeft, bpTopRight, bpBottomLeft, bpBottomRight);
THidePanel = class(TPanel)
private
FActivateButton: TButton;
FButtonPosition: TButtonPosition;
FExpandState: Boolean;
FOldAlign: TAlign;
FOldWidth: Integer;
FOnActivateBtnClick: TNotifyEvent;
FWorkingPanel: TPanel;
procedure ActivateButtonClick(Sender: TObject);
procedure SetButtonPosition(Value: TButtonPosition);
protected
function CanResize(var NewWidth, NewHeight: Integer): Boolean; override;
procedure Resize; override;
public
constructor Create(AOwner: TComponent); override;
procedure SetState(AState: Boolean);
published
property ButtonPosition: TButtonPosition read FButtonPosition
write SetButtonPosition default bpTopRight;
property OnActivateButtonClick: TNotifyEvent read FOnActivateBtnClick
write FOnActivateBtnClick;
end;
procedure Register;
implementation
procedure Register;
begin
RegisterComponents('Samples', [THidePanel]);
end;
{ THidePanel }
constructor THidePanel.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FWorkingPanel := TPanel.Create(Self);
FWorkingPanel.Caption := '';
FWorkingPanel.SetBounds(BorderSize, BorderSize, Width - 2 * BorderSize,
Height - 2 * BorderSize);
FWorkingPanel.Anchors := [akLeft, akTop, akRight, akBottom];
FWorkingPanel.Parent := Self;
FActivateButton := TButton.Create(Self);
FActivateButton.Caption := '<';
FActivateButton.OnClick := ActivateButtonClick;
FActivateButton.Width := BorderSize;
FActivateButton.Height := BorderSize;
FActivateButton.Parent := Self;
SetButtonPosition(bpTopRight);
end;
procedure THidePanel.ActivateButtonClick(Sender: TObject);
begin
FExpandState := not FExpandState;
SetState(FExpandState);
if Assigned(FOnActivateBtnClick) then
FOnActivateBtnClick(Self);
end;
procedure THidePanel.SetButtonPosition(Value: TButtonPosition);
begin
if FButtonPosition <> Value then
begin
FButtonPosition := Value;
case FButtonPosition of
bpTopLeft:
begin
FActivateButton.Left := 0;
FActivateButton.Top := 0;
FActivateButton.Anchors := [akLeft, akTop];
end;
bpTopRight:
begin
FActivateButton.Left := Width - BorderSize;
FActivateButton.Top := 0;
FActivateButton.Anchors := [akRight, akTop];
end;
bpBottomLeft:
begin
FActivateButton.Left := 0;
FActivateButton.Top := ClientWidth - BorderSize;
FActivateButton.Anchors := [akLeft, akBottom];
end;
bpBottomRight:
begin
FActivateButton.Top := ClientWidth - BorderSize;
FActivateButton.Left := Width - BorderSize;
FActivateButton.Anchors := [akRight, akBottom];
end;
end;
end;
end;
procedure THidePanel.SetState(AState: Boolean);
begin
if AState then
begin
FActivateButton.Caption := '>';
FOldAlign := Align;
if FOldAlign = alClient then
Align := alLeft;
Width := BorderSize;
end
else
begin
FActivateButton.Caption := '<';
if FOldAlign = alClient then
Align := FOldAlign
else
Width := FOldWidth;
end;
end;
procedure THidePanel.Resize;
begin
if not FExpandState then
FOldWidth := Width;
inherited Resize;
end;
function THidePanel.CanResize(var NewWidth, NewHeight: Integer): Boolean;
begin
Result := inherited CanResize(NewWidth, NewHeight);
if FExpandState then
NewWidth := BorderSize;
end;
end.
测试代码:
unit Unit1;
interface
uses
Controls, Forms, Unit2, ExtCtrls;
type
TForm1 = class(TForm)
procedure FormClick(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormClick(Sender: TObject);
begin
with THidePanel.Create(Self) do
begin
Align := alLeft;
Parent := Self;
end;
with TSplitter.Create(Self) do
begin
Left := 200;
Parent := Self;
end;
with THidePanel.Create(Self) do
begin
Align := alClient;
Parent := Self;
end;
end;
end.